leftEdgeUnsafe

Returns the positional index of the left edge of a tree t
within a given root, as defined by the size of the yield of all
material preceding t.
This method returns -1 if no path is found, rather than exceptioning.

rightEdgeUnsafe

Returns the positional index of the right edge of a tree
t within a given root, as defined by the size of the yield
of all material preceding t plus all the material
contained in t.
This method returns root.yield().size() + 1 if no path is found, rather than exceptioning.

toFlatTree

Turns a sentence into a flat phrasal tree.
The structure is S -> tag*. And then each tag goes to a word.
The tag is either found from the label or made "WD".
The tag and phrasal node have a StringLabel.

Parameters:

s - The Sentence to make the Tree from

Returns:

The one phrasal level Tree

toFlatTree

Turns a sentence into a flat phrasal tree.
The structure is S -> tag*. And then each tag goes to a word.
The tag is either found from the label or made "WD".
The tag and phrasal node have a StringLabel.